The new product is among reductions of up to 0.25% which the society is making to rates across its range of 75% LTV mortgages.
Chelsea product manager Chris Smith said: "We've reduced our rates as we aim to be competitive across our mortgage range at all LTVs.
"As well as the 1.99% two year fixed rate mortgage at 75% LTV, we also have cut our five year fixed rate mortgage from 2.84% to 2.69%
"Our 75% LTV mortgages are available in branch, online or by telephone so borrowers can choose the channel that suits them best to apply."
The 1.99% mortgage has an offset equivalent of 2.19% and each product has a £1,545 fee.
Mortgages in Chelsea's 75% LTV range include £745, £345 and £245 completion fee products and mortgages with incentives, including cashback of up to £500 or free legal and valuation assistance, for borrowers seeking to minimise their upfront costs.
All Chelsea Building Society mortgage products have an offset equivalent, priced 0.20% above the standard mortgage product.
